Today, WW-II bombers and a new machine for a
Shakespearean scholar. The University of Houston's
College of Engineering presents this series about the
machines that make our civilization run, and the
people whose ingenuity created them.

Historian Richard Altick
tells about Charlton Hinman, a literary scholar who
spent four years in the Navy during WW-II. An
ongoing riddle in his field had to do with a set of
nine Shakespeare plays. In Shakespeare's time,
plays were printed individually and sold unbound.
An owner might eventually take a random set of
plays to a bookbinder and have them bound into a
volume. But these nine plays, with dates between
1600 and 1619, repeatedly showed up in the same
volume. That made no sense.

Scholars had used photography on the problem. After
carefully measuring photos of the pages, they'd
cooked up a theory: the printer, who'd been barred
by law from printing these plays, did print them
all in 1619. But he backdated most of them. That
way he was able to sell them as though they were
old copies.

The detective work had meant searching almost
identical pages for tiny differences -- like nicks
on individual pieces of type. But the mind-numbing
work was still inconclusive. Hinman wondered if the
job couldn't somehow be automated!

Meanwhile, American bomber squadrons were asking an
oddly related question: how could they spot bomb
damage from photos? Before and after bombing raids,
scout planes would photograph the area from the
same altitude and angle. But how to compare photos?

Then someone had a bright idea. Take the two
pictures and play them on a screen in rapid
alternation. The result would be one clear picture,
except for any spot that changed from one picture
to the next. It would appear blurred on the screen.

Nice idea, but it was next to impossible to get two
photos from the same place in the sky. It didn't
work, but it gave Hinman his answer. You couldn't
get identical pictures of Earth's surface, but
maybe you could get identical photos of printed
pages.

After the war, in Washington's Folger Library,
Hinman built an apparatus from packing crates,
erector sets, and cardboard. It sort of worked. But
the old aerial bombing problem lingered. Even book
pages are hard to photograph precisely. Then Hinman
entered the second stage of the inventive process
-- he made a leap of creative simplification.

The fact that his idea had been triggered by
photography didn't mean he had to keep using
photography. He realized he could simply line up
the two actual texts, side by side, and view them
in rapid alternation through an optical system.

So he invented the machine we still use to do that
task: the Hinman collator. With it, he ended debate
over the nine Shakespeare plays. But more than
that, Charlton Hinman had managed to beat a flawed
sword into -- a most unexpected plowshare.

I'm John Lienhard at the University of Houston,
where we're interested in the way inventive minds
work.

(Theme music)

R.D. Altick, The Scholar Adventurers.
New York: The Free Press, 1966, Chapter VII, The
Scholar and the Scientist. I am most grateful to
attorney Stephen Hamilton of Houston for providing
the intriguing Altick source.

As an example of the
problem of comparing
texts, try comparing these
two passages, one
above and one below, in an attempt
to discern
what four things are different on either one.
You
will find that it's harder to identify
the differen-
ces than you would expect.

As an example of the problem
of comparing
texts, try comparing these two
passages, one
below and one above, in an attempt to
discern
what five things are different in either one.
You
will find that its harder to
identify the differen-
ces than one would
except.